Machine for powdering plates to be etched



Aug. 13, 1929. w, LOGAN 1,724,671

MACHINE FOR POWDERING PLATES Tb BE ETCHED Filed June 10, 1926 2Sheets-Sheet 1 Aug. 13, 1929. w. J. LOGAN I f 1,724,671 7 MACHINE FORPOWDERING PLATE S TO BE ETQHED Filed June 1 0, 1926 E Sheets-Sheet' 2Patented Aug. 13, 1929.

UNITED STATES WILLIAM J. LOGAN, OF CLEVELAND, OHIO.

MACHINE FOR POWDERIN G PLATES TO BE ETCHED.

Application filed June 10,

This invention relates to machines for powdering plates to be etched,and has for its main object to provide a machine of simple compactconstruction, which is adapted to carry out the successive steps ofbrushing and heating at the will of the operator after the plates havebeen manually covered with powder.

ith the above and other objects in view as will be understood, theinvention will be hereinafter fully described as illustrated in theaccompanying drawings, and the novel features thereof will be distinctlypointed out in the appended claims.

y In the drawings similar characters of reference denote correspondingparts.

Figure 1 is a front elevation of a machine constructed in accordancewith my invention,

Fig. 2 is an elevation looking at the lefthand end of the machine,

Fig. 3 is a plan View of Fig. 1, the hood being removed to better showthe construction,

Fig. 4 is a similar view to Fig. 2 looking at the right hand end of themachine,

Fig. 5 illustrates the mechanism for connecting and disconnecting theplate supporting rack to the threaded shaft, the lever '30 being inengagement with the threaded shaft,

Fig. 6 is a rear view of the upper part of the arm shown in Fig. 5, and

Fig. 7 is a similar view to Fig. 5, the lever being disengaged from thethreaded shaft.

Referring to the drawings 1 represents a suitable frame for supportingthe stove for heating the plates to be etched. The stove consists of aplurality of gas burners indicated by 2, which gas burners are connectedto a manifold 3 and this to a horizontal pipe 4, a downwardly extendingpipe 5 and rearwardly extending pipe 6, which is adapted to be connectedto the gas supply pipe. An automatically closing shut-off valve 7 isprovided in the pipe 6, and this valve is opened to admit gas to theburners 2 by means of a foot-lever 8 which is pivoted to the frame at 9and connected to the stem of said valve by a'link 10. The foot-lever 8is provided with a pedal 11. An electrical igniting device 12 adapted tobe actuated by the operator throwing a conveniently placed switch 13 isemployed for quickly lighting the gas from the burners. Said stove frameis placed at the end of a suitable frame 14 for supporting 1926. SerialNo. 114,959.

the mechanism now to be described. This frame 14, as does also the topof the frame 1 of the stove, supports a pair of angle irons 15 and 16 toprovide rails for slidably supporting a rack 17 consisting of side bars18 and 19 connected together by transverse bars 20, upon which are laidthe plates after being powdered to be brushed and the powder burnedthereto. Said plate is indicated by 21. The bars 20 are recessed ornotched at 22 to permit the passage of the flames and heat from theburners of the stove under said plate. The end uprights of the frame 14project above the tops thereof as at 2324 and 2526, and uprights 2728are arranged opposite the uprights 23-24. Fixed to the inner faces ofthe uprights 23-27 and 2428 are pairs of bearings indicated by 29 and30, which support transverse shafts 31 and 32 having fixed theretopulleys 33 and 34, over which pass an endless belt 35. Transverselyarranged brushes 36 are suitably fixed to the belt 35 for brush ing thepowdered plate 21 as it passes thereunder. The downward pressure of thebrushes 36 upon the powdered plate 21 tends to force the belt 35upwardly and for preventing this upward movement of the belt, a guide 37supported by the uprights 27 and 28 is provided at the inner side of theunder side of said belt which slides thereunder.

The rack 17 which is normally over the burners 2 of the stove, is firstmoved quickly to the right for receiving the powdered plate 21 and thenreturned slowly carrying the powdered plate under the transverselytraveling brushes 36 to its original position over the stove by means ofthe following described mechanism. The shaft 32 is extended and itsother end is rotatably supported in a bearing 38 fixed to the uprightextension 26 of the frame. The extension of the shaft 32 is threaded at39, and fixed to its outer end is a toothed-wheel 40, over which passesachain 41 driven by an electric motor 42. Said motor is supported by aplatform 43 of the frame and it is controlled by the operator by meansof a conveniently located switch 44. An arm 45 is fixed at 46 to the endtransverse bar of the rack 17, and formed integrally with its upperextension 47 is a pair of rearwardly extending lugs 48 and 49, which areprovided with transverse openings at 50 for loosely receiving andsliding over the threaded shaft 39. For connecting and disconnecting themove'ment'of the rack 17.

threaded shaft 39 to the arm 47, a depending lever 51 is pivoted at 52between a pair of cars 53 and 54 formed integrally with said extensionof said arm, and a blade or tooth 55 forming a part of said lever isadapted to enter the space between the lugs 13 and 19 and between theteeth of said shaft. A suitable weight 56 at the freeend of the lever 51tends to hold its blade or tooth 55 in firm engagement with the threadedshaft 39, and when so engaged, the arm 47 is forced forwardly or to theleft and consequently the rack 17 is moved in the same direction. Inorder to move the rack 17 rearwardly or to the right quickly, which isaccomplished by the action of a weight, the free end of the lever 51 isfirst raised upwardly a sufficient distance to disconnect its blade ortooth from the threaded shaft 39 but not clear of the lugs 18 and 49,and then held in said position, all as will now be described. A rod. orshaft 57 is rotatably supported in bearings 58 and 59 fixed to theuprights 26 and 28 of the frame 14, and a pair of arms 60 and 61 arerigidly connected to said shaft and to their ends is fixed bar 62 whichis adapted to engage and serve as a guide for the lever 51. A lever-arm63 is fixed to the end of the shaft 57, and its free end is pivoted to aconnecting-rod 64 having its other end pivoted to a foot-lever 65, whichis pivota-lly supported at 65 to the frame. The foot-lever '65 isprovided with a pedal 67. When the operator presses upon the pedal 67,the lever 51 is raised, and the arm 47 being disconnected from and looseupon the threaded shaft 39, permits the action of a suitable weight 68,which is attached to a cable 69 passing over a pulley 70 and under apulley 71 and connected to a coiled spring 72 havingits other endconnected to the rack 17, to return said rack to its rear or righthandposition. A stop 73 is adapted to limit the upward movement of theweight 68 before the rack 17 reaches the end of its forward or left-handmovement, so that there will be some tension upon the coiled spring 72for startingthe rack rearwardly or to the right upon the disconnectingof the blade or tooth of the lever 51 from the threaded shaft 39. Stops,as indicated by 74. are fixed to the rails 15 and 16 for limitingthereturn After heating the plate 21over the stove to bake the powderthereon, and before applyingthereto another coating of powder, saidplate is cooled quichly by means of air supplied by a fan 75, which isdirectly connected to and driven by an electric motor 7 6. An air pipe'77 leads from the 'fan 75'to the underside of he plate 21. Aconveniently located'switch 78 is provided foroperatingtheelectric motor7 6.

The u'pperpart of the frame 14 is preferably enclosed by a suitable hoodas indieated'at 79,which is provided wit-han pening at 80 for passin theplates therethrough to the rack 17 after being manually sprinkled withpowder, and an opening at 81 for permitting said raclr to pass in andout thereof. A drawer 82 is slidably supported upon rails 83 and 84:fixed to the uprights of the frame let for holding the powder to besprinkled upon the plates, and also for receivingthe surplus powderbrushed from the plates.

In practice the rack 17 is over the burners 2 of the stove, ano theblade or tooth 55 of the lever 51 is in engagement with the threadedshaft 39. The operator sprinkles powder taken from the drawer 82 uponthe plate 21, and then steps upon the pedal 25, which causes the bladeor tooth 55 to be lifted free of the threaded shaft 39 and permits theweight 68 to force the rack 17 rearwardly or to the right and over thepowder drawer 82. He then lays the plate upon the rack 17 and releasesthe pedal 25, which causes the blade or tooth 55 to again engage thethreaded shaft 39. Upon starting the electric motor 12 by means of theswitch 44s, the rack 17 is forced forwardly or to the left therebycarrying the plate 21 under the transversely traveling brushes '36 forbrushing the surplus powder therefrom. lVhen the rack 17 with the powderthereon is over the burners 2 of the stove, the operator stops theelectric motor 42. He then steps upon the pedal 11 thereby opening thevalve 7 f r admitting gas to the burners 2 of the stove, and at the sametimeoperates switch 13 to ignite the from the burners for burning thepowder to the plate. After the baking of the powder, the gas isextinguished by releasing the pedal 11, and the other electric motor 76started by means of the switch 78 to cause the fan 75 to force air uponthe plate and thereby cool the same, after which said electric motor isstopped. The plates have now been powdered once, and as it is necessaryto powderthe plates several times, said successive steps are repeatedafter each sprinkling of the powder upon the plate.

From the drawings and description it will be seen that by means of thiscompact and conveniently operated machine, the successive stepsnecessary to the elficient powdering of plates to be etched may becarried out quickly. I

Having fully described my invention what 1 claim is:

1. In a machine for powdering plates to be etched, the combinationof arack, a stove, brushes, the rack being adapted to move under the brushesand over the stove, the brushes being adapted to move as the rack in resthereunder, means for moving the rack slowly in one direction, means"for moving the brushes, and means for moving the rack quickly 111 theother direction for returningt 1e rack to its original position.

moves thereunder,

2. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under the brushesand over the stove, the brushes being adapted to move as the rack movesthereunder, a rotatably supported shaft, means for rotating the shaft,means for moving the rack by rotation of the shaft, and means for movingthe brushes by the rotation of the shaft.

3. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under the brushesand over the stove, the brushes being adapted to move as the rack arotatably supported shaft, means for rotating the shaft, means formoving the rack slowly in one direction by the rotation of the shaft,means for moving the brushes by the rotation of the shaft, and means formoving the rack quickly in the other direction for returning the rack toits original position.

4. In a machine for powdering plates to be etched, the combination of arack, a stove, bruches being adapted to move as the rack der the brushesand over the stove, the brushes being adapted to move as the rock movesthereunder, a rotatably supported shaft, means for rotating the shaft,the shaft being threaded, an arm fixed to the rack, means whereby thearm may be connected to and disconnected from the threaded shaft, meansfor moving the brushes by the rotation of the shaft, and means formoving the rack upon disconnection of the arm from the shaft.

5. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under the brushesand over the stove, the brushes being adapted to move as the rack movesthereunder, a rotatably supported shaft. means for rotating the shaft,the shaft being threaded, an arm fixed to the rack, means whereby thearm may be connected and disconnected from the threaded shaft, means formoving the brushes by the rotation of the shaft, and means forimpartingto the rack quick movement in the other direction upon disconnection ofthe arm from the shaft for returnin the rack to its original position.

6. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under thebrushes, and over the stove, the brushes being adapted to move as therack moves thereunder, a rotatably supported shaft, means for rotatingthe shaft, the shaft being threaded, an arm fixed to the rack, a leverpivoted to the arm and adapted to engage the threaded shaft for movingthe rack in one direction. means for disengaging the lever from thethreaded shaft and holding it in the disconnected position, and meansfor quickly returning the rack upon disconnection of the lever from theshaft.

7. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under thebrushes, and over the stove, the brushes being adapted to move as therack moves thereunder, a rotatably supported shaft, means for rotatingthe shaft, the shaft being threaded, an arm fixed to the rack, adepending lever pivoted to the arm. the lever having a blade adapted toengage the thread ed shaft, a rotatably supported rod, arms fixed to therod, a bar fixed to the arm adapted to engage said lever and serve as aguide therefor, and means for rocking said rod to actuate said bar forraising said lever out of engagement with said threaded shaft, and meansfor causing movement of said rack in the other direction upon theraising of said lever out of engagement with said threaded shaft.

8. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under the brushesand over the stove, the brushes being adapted to move as the rack movesthereunder, a rotatably supported shaft, means for rotating the shaft,the shaft being threaded, an arm means whereby the arm may be connectedand disconnected from the threaded shaft, means for connecting the armto the threaded shaft to cause movement of the rack in one direction, acable connected to the rack, the cable passing over pulleys, a weightattached to the cable, a coiled spring arranged in the cable, and a stopfor limiting the movement of the weight when the rack is moved by theshaft to exert tension upon said coiled spring for starting the rackupon disengagement of the arm from the threaded shaft.

9. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under the brushesand over the stove, pulleys, a belt carried by pulleys, brushes carriedby the belt, one of the pulleys being fixed to a rotatably supportedshaft, means for rotating the shaft, means for causing slow movement ofthe rack in one direction by the rotation of the shaft, and means forquickly moving the rack in the opposite direction.

10. In a machine for powdering plates to be etched, the combination of arack, a stove, brushes, the rack being adapted to move under the brushesand over the stove, pulleys, a belt carried by pulleys, brushes carriedby the belt, one of the pulleys being fixed to a rotatably supportedshaft, means for rotat ing the shaft, the shaft being threaded, an armfixed to the rack, a lever pivoted to the arm and adapted to engage thethreaded Shaft for moving the rack in one direction,

fixed to the rack,

nected position, and means ineans for disengaging the lever from thethreaded shaft and holding it in the disconfor returning the rack upondisconnection of the lever from the shaft.

11. In a machine for powdering plates to be etched, the combination of aframe, a stove supported by the frame, a rack slidably sup ported by theframe, brushes adapted to travel transversely of the movement of therack, the brushes being carried by an endless belt, the belt passingaround the pulleys, one of the pulleys being fixed to shafts rotatablysupported by the frame, one of the shafts being extended, the extensionof the shaft being threaded, means for rotating said extended siaft, anarm fixed to the rack, a depending link pivoted to the arm, thelinkhaving a blade adapted to engage the threaded shaft, a rod rotatablysupported by the frame and extended longitudinally, arms fixed to therod, a bar fixed to the arms adapted to engage said lever and serve as aguide, means for rocking said rod to actuate said bar for raising saidlever out of engagement with said threaded shaft, and means for causingthe movement of said rack in the other direction upon the raising ofsaid lever outef engagement with said threaded shaft.

In testimony whereof I my signature.

WiLLIAM J. LOGAN.

